A type of cell in the thyroid. C cells make calcitonin, a hormone that helps control the calcium level in the blood.

CA 19-9 assay

A test that measures the level of CA 19-9 in the blood. CA 19-9 is a tumor marker released into the bloodstream from both cancer cells and normal cells. Higher than normal amounts of CA 19-9 in the blood can be a sign of gallbladder or pancreatic cancer or other conditions.

CA-125

A substance sometimes found in an increased amount in the blood, other body fluids, or tissues and that may suggest the presence of some types of cancer.

CA-125 test

A blood test that measures the level of CA-125, a substance found in blood, other body fluids and some tissues. Increased levels of CA-125 may be a sign of cancer.

cachexia (ka-KEK-see-a)

Loss of body weight and muscle mass, and weakness that may occur in patients with cancer, AIDS, or other chronic diseases.

CAD

Coronary artery disease. A disease in which there is a narrowing or blockage of the coronary arteries (blood vessels that carry blood and oxygen to the heart). CAD is usually caused by atherosclerosis (a build up of fatty material and plaque inside the coronary arteries). The disease may cause chest pain, shortness of breath during exercise, and heart attacks. The risk of CAD is increased by having a family history of CAD before age 50, older age, smoking tobacco, high blood pressure, high cholesterol, diabetes, lack of exercise, and obesity. Also called coronary heart disease.

cadmium (KAD-me-um)

A metallic element that occurs naturally in tiny amounts in air, water, soil, and food. It is a byproduct of zinc refining, and is used to make batteries, pigments, plastics, alloys, and electroplate. It is also found in cigarette smoke. Exposure to high levels of cadmium may cause certain cancers and other health problems.

calcification

Deposits of calcium in the tissues. Calcification in the breast can be seen on a mammogram, but cannot be detected by touch. There are two types of breast calcification, macrocalcification and microcalcification. Macrocalcifications are large deposits and are usually not related to cancer. Microcalcifications are specks of calcium that may be found in an area of rapidly dividing cells. Many microcalcifications clustered together may be a sign of cancer.

calcitonin

A hormone formed by the C cells of the thyroid gland. It helps maintain a healthy level of calcium in the blood. When the calcium level is too high, calcitonin lowers it.

calcitriol (kal-sih-TREE-ol)

The active form of vitamin D. Calcitriol is formed in the kidneys or made in the laboratory. It is used as a drug to increase calcium levels in the body in order to treat skeletal and tissue-related calcium deficiencies caused by kidney or thyroid disorders.

calcium (KAL-see-um)

A mineral found in teeth, bones, and other body tissues.

calcium carbonate

A mineral taken primarily as a supplement to prevent osteoporosis. It is also being studied for cancer prevention.

caloric intake

Refers to the number of calories (energy content) consumed.

calorie

A measurement of the energy content of food. The body needs calories as "fuel" to perform all of its functions, such as breathing, circulating the blood, and physical activity. When a person is sick, their body may need extra calories to fight fever or other problems.

CAM

Complementary and alternative medicine. Forms of treatment that are used in addition to (complementary) or instead of (alternative) standard treatments. These practices generally are not considered standard medical approaches. Standard treatments go through a long and careful research process to prove they are safe and effective, but less is known about most types of CAM. CAM may include dietary supplements, megadose vitamins, herbal preparations, special teas, acupuncture, massage therapy, magnet therapy, spiritual healing, and meditation.

Campath-1H

A monoclonal antibody used to treat leukemia. Monoclonal antibodies are laboratory-produced substances that can locate and bind to cancer cells. Also called alemtuzumab.

camphor

A substance that comes from the wood and bark of the camphor tree or is made in the laboratory. It has a very unique smell and taste and is used in commercial products (for example, mothballs). Camphor is used in topical anti-infective and anti-pruritic (anti-itching) agents.

camptothecin

An anticancer drug that belongs to the family of drugs called topoisomerase inhibitors.

camptothecin analog

An anticancer drug related in structure to camptothecin, a topoisomerase inhibitor. One such drug is aminocamptothecin.

cancer

A term for diseases in which abnormal cells divide without control. Cancer cells can invade nearby tissues and can spread through the bloodstream and lymphatic system to other parts of the body. There are several main types of cancer. Carcinoma is cancer that begins in the skin or in tissues that line or cover internal organs. Sarcoma is cancer that begins in bone, cartilage, fat, muscle, blood vessels, or other connective or supportive tissue. Leukemia is cancer that starts in blood-forming tissue such as the bone marrow, and causes large numbers of abnormal blood cells to be produced and enter the bloodstream. Lymphoma and multiple myeloma are cancers that begin in the cells of the immune system.

Cancer Information Service

CIS. The Cancer Information Service is the National Cancer Institute's (NCI) link to the public, interpreting and explaining research findings in a clear, understandable manner and providing personalized answers to questions about cancer. Talk with CIS staff toll-free by calling 1-800-4-CANCER (1-800-422-6237), or reach them online through LiveHelp, NCI's instant messaging service, at http://cancer.gov.

cancer of unknown primary origin

A case in which cancer cells are found in the body, but the place where the cells first started growing (the origin or primary site) cannot be determined.

cancer vaccine

A vaccine designed to prevent or treat cancer.

candidiasis (kan-dih-DY-uh-siss)

A condition in which Candida albicans, a type of yeast, grows out of control in moist skin areas of the body. It is usually a result of a weakened immune system, but can be a side effect of chemotherapy or treatment with antibiotics. Thrush usually affects the mouth (oral thrush); however, rarely, it spreads throughout the entire body. Also called candidosis or thrush.

candidosis (kan-dih-DOH-siss)

A condition in which Candida albicans, a type of yeast, grows out of control in moist skin areas of the body. It is usually a result of a weakened immune system, but can be a side effect of chemotherapy or treatment with antibiotics. Thrush usually affects the mouth (oral thrush); however, rarely, it spreads throughout the entire body. Also called candidiasis or thrush.

CAP-1

Carcinoembryonic antigen peptide-1. A protein that can stimulate an immune response.

capecitabine

A drug that is used in the treatment of cancer. It belongs to the family of drugs called antimetabolites.

capillary

The smallest type of blood vessel. A capillary connects an arteriole (small artery) to a venule (small vein) to form a network of blood vessels in almost all parts of the body. The wall of a capillary is thin and leaky, and capillaries are involved in the exchange of fluids and gases between tissues and the blood.

capillary leak syndrome

A condition in which fluid and proteins leak out of tiny blood vessels and flow into surrounding tissues, resulting in dangerously low blood pressure. Capillary leak syndrome may lead to multiple organ failure and shock.

capsaicin

A component of certain plants, including cayenne and red pepper, used topically for peripheral nerve pain. Also being studied for controlling mucositis pain after chemotherapy and radiation therapy.

captopril

A drug used to treat high blood pressure that is also being studied in the prevention of side effects caused by radiation therapy used in the treatment of cancer. It belongs to the family of drugs called ACE inhibitors.

carbendazim

An anticancer drug that belongs to the family of drugs called antifungal agents.

carbogen

An inhalant of oxygen and carbon dioxide that increases the sensitivity of tumor cells to the effects of radiation therapy.

carbohydrate

A sugar molecule. Carbohydrates can be small and simple (for example, glucose) or they can be large and complex (for example, polysaccharides such as starch, chitin or cellulose).

carbon-11 acetate

A radioactive form of carbon that is used in positron emission tomography (PET) scanning.

carboplatin

An anticancer drug that belongs to the family of drugs called platinum compounds.

carboxyamidotriazole

An anticancer drug that belongs to the family of drugs called angiogenesis inhibitors.

carboxypeptidase-G2

A bacterial enzyme that is used to neutralize the toxic effects of methotrexate. It belongs to the family of drugs called chemoprotective agents.

carcinoembryonic antigen (KAR-sin-o-EM-bree-ON-ik ANT-i-jun)

CEA. A substance that is sometimes found in an increased amount in the blood of people who have certain cancers, other diseases, or who smoke. It is used as a tumor marker for colorectal cancer.

carcinoembryonic antigen peptide-1

CAP-1. A protein that can stimulate an immune response to certain tumors.

carcinogen (kar-SIN-o-jin)

Any substance that causes cancer.

carcinogenesis

The process by which normal cells are transformed into cancer cells.

carcinoid (KAR-sin-oyd)

A slow-growing type of tumor usually found in the gastrointestinal system (most often in the appendix), and sometimes in the lungs or other sites. Carcinoid tumors may spread to the liver or other sites in the body, and they may secrete substances such as serotonin or prostaglandins, causing carcinoid syndrome.

carcinoid syndrome (KAR-sin-oyd)

A combination of symptoms caused by the release of serotonin and other substances from carcinoid tumors of the gastrointestinal tract. Symptoms may include flushing of the face, flat angiomas (small collections of dilated blood vessels) of the skin, diarrhea, bronchial spasms, rapid pulse, and sudden drops in blood pressure.

carcinoma (KAR-sih-NOH-muh)

Cancer that begins in the skin or in tissues that line or cover internal organs.

carcinoma in situ (KAR-sih-NOH-muh in SYE-too)

Cancer that involves only cells in the tissue in which it began and that has not spread to nearby tissues.

carcinomatosis

A condition in which cancer is spread widely throughout the body, or, in some cases, to a relatively large region of the body. Also called carcinosis.

carcinosarcoma

A malignant tumor that is a mixture of carcinoma (cancer of epithelial tissue, which is skin and tissue that lines or covers the internal organs) and sarcoma (cancer of connective tissue, such as bone, cartilage, and fat).

carcinosis

A condition in which cancer is spread widely throughout the body, or, in some cases, to a relatively large region of the body. Also called carcinomatosis.

carcinostatic (KAR-sin-o-STAT-ik)

Pertaining to slowing or stopping the growth of cancer.

cardiac

Having to do with the heart.

cardin

Cnicus benedictus. A plant whose leaves, stems, and flowers have been used in some cultures to treat certain medical problems. Cardin may have anti-inflammatory and anticancer effects. Also called blessed thistle, St. Benedict's thistle, holy thistle, and spotted thistle.

cardiopulmonary

Having to do with the heart and lungs.

cardiotoxicity

Toxicity that affects the heart.

cardiovascular

Having to do with the heart and blood vessels.

carmustine

An anticancer drug that belongs to the family of drugs called alkylating agents.

carnitine

A substance made in the muscles and liver, and also found in certain foods such as meat, poultry, fish, and some dairy products. The body needs carnitine to make energy from fat.

carotenoid

A substance found in yellow and orange fruits and vegetables and in dark green, leafy vegetables. Carotenoids may reduce the risk of developing cancer.

carotid artery (kuh-RAH-tid AR-tuh-ree)

A major artery that carries blood from the heart to the head. There is a carotid artery on each side of the neck, and each one splits into two branches. The interior branch carries blood to the brain and eyes, and the exterior branch carries blood to the face, tongue, and outside parts of the head.

cartilage (KAR-tih-lij)

A tough, flexible tissue that lines joints and gives structure to the nose, ears, larynx, and other parts of the body.

carzelesin

An anticancer drug that belongs to the family of drugs called alkylating agents.

case report

A detailed report of the diagnosis, treatment, and follow-up of an individual patient. Case reports also contain some demographic information about the patient (for example, age, gender, ethnic origin).

case series

A group or series of case reports involving patients who were given similar treatment. Reports of case series usually contain detailed information about the individual patients. This includes demographic information (for example, age, gender, ethnic origin) and information on diagnosis, treatment, response to treatment, and follow-up after treatment.

case-control study

A study that compares two groups of people: those with the disease or condition under study (cases) and a very similar group of people who do not have the disease or condition (controls). Researchers study the medical and lifestyle histories of the people in each group to learn what factors may be associated with the disease or condition. For example, one group may have been exposed to a particular substance that the other was not. Also called a retrospective study.

caspofungin acetate

A drug used to prevent or treat infections caused by a fungus (a type of microorganism). It belongs to the family of drugs called antifungal agents.

Castleman's disease

A rare disorder in which noncancerous growths develop in lymph node tissue.

castration

Removal or destruction of the testicles or ovaries using radiation, surgery, or drugs. Medical castration refers to the use of drugs to suppress the function of the ovaries or testicles.

CAT scan

Computerized axial tomography scan. A series of detailed pictures of areas inside the body, taken from different angles; the pictures are created by a computer linked to an x-ray machine. Also called computed tomography (CT scan) or computerized tomography.

cataract (KA-tuh-RAKT)

A condition in which the lens of the eye becomes cloudy. Symptoms include blurred, cloudy, or double vision; sensitivity to light; and difficulty seeing at night. Without treatment, cataracts can cause blindness. There are many different types and causes of cataracts. They may occur in people of all ages, but are most common in the elderly.

catechol

A chemical originally isolated from a type of mimosa tree. Catechol is used as an astringent, an antiseptic, and in photography, electroplating, and making other chemicals. It can also be man-made.

catheter (KATH-i-ter)

A flexible tube used to deliver fluids into or withdraw fluids from the body.

cauterization (KAW-ter-ih-ZAY-shun)

The destruction of tissue with a hot instrument, an electrical current, or a caustic substance.

cauterize (KOT-uh-rize)

To destroy tissue with a hot instrument, an electrical current, or a caustic substance. This process may be used to kill certain types of small tumors or to seal off blood vessels to stop bleeding.

CBC

Complete blood count. A test to check the number of red blood cells, white blood cells, and platelets in a sample of blood. Also called blood cell count.

cBR96-doxorubicin immunoconjugate

A substance that is being studied in the treatment of cancer. It combines a monoclonal antibody with the anticancer drug doxorubicin. Monoclonal antibodies are substances that are made in the laboratory and that can locate and bind to cancer cells. cBR96-doxorubicin immunoconjugate belongs to the family of drugs called antibody drug conjugates. Also called SGN-15.

CC-1088

A drug that is being studied in the treatment of cancer. It is similar but not identical to thalidomide. CC-1088 belongs to the family of drugs called angiogenesis inhibitors.

CC-49

A type of monoclonal antibody used in cancer detection or therapy. Monoclonal antibodies are laboratory-produced substances that can locate and bind to cancer cells.

CC49-streptavidin

A substance that is being studied in the treatment of cancer. It is made by combining the monoclonal antibody CC49 with a chemical called streptavidin. It can find tumor cells that have the protein TAG-72 on their surface, including colon, prostate, breast, and ovary cancer cells. After CC49-streptavidin binds to cancer cells, a radioactive compound called yttrium Y 90 DOTA-biotin will find those cells and kill them.

CC-5013

A substance that is being studied in the treatment of cancer. It is similar to thalidomide. It belongs to the family of drugs called angiogenesis inhibitors. Also called lenalidomide.

CC-8490

A substance that is being studied in the treatment of brain cancer. It belongs to the family of drugs called benzopyrans.

CCI-779

A substance that is being studied in the treatment of cancer. It belongs to the family of drugs called rapamycin analogs. Also called temsirolimus.

CD34 antigen

A protein found on the surface of some bone marrow and blood cells.

CD40-ligand

A substance that is being studied in the treatment of cancer. It binds to certain immune cells and may suppress cancer growth.

CEA

Carcinoembryonic antigen. A substance that is sometimes found in an increased amount in the blood of people who have certain cancers, other diseases, or who smoke. It is used as a tumor marker for colorectal cancer.

CEA assay

A laboratory test to measure carcinoembryonic antigen (CEA), a substance that is sometimes found in an increased amount in the blood of people who have certain cancers.

cecum (SEE-kum)

A pouch that forms the first part of the large intestine. It connects the small intestine to the colon, which is part of the large intestine.

cefepime

A drug used to treat infection. It belongs to the family of drugs called cephalosporin antibiotics.

cefixime

An antibiotic drug used to treat infection. It belongs to the family of drugs called cephalosporins.

ceftriaxone

A drug used to treat infection. It belongs to the family of drugs called cephalosporin antibiotics.

celecoxib (sel-a-KOX-ib)

A drug that reduces pain. Celecoxib belongs to the family of drugs called nonsteroidal anti-inflammatory agents. It is being studied in the prevention of cancer.

celiac disease

A digestive disease that is caused by an immune response to a protein called gluten, which is found in wheat, rye, barley, and oats. Celiac disease damages the lining of the small intestine and interferes with the absorption of nutrients from food. A person with celiac disease may become malnourished no matter how much food is consumed.

cell

The individual unit that makes up the tissues of the body. All living things are made up of one or more cells.

cell differentiation

The process during which young, immature (unspecialized) cells take on individual characteristics and reach their mature (specialized) form and function.

cell motility

The ability of a cell to move.

cell proliferation

An increase in the number of cells as a result of cell growth and cell division.

cell respiration

A chemical process in which oxygen is used to make energy from carbohydrates (sugars). Also called oxidative metabolism, aerobic metabolism, or aerobic respiration.

cell-cycle regulation

Any process that controls the series of events by which a cell goes through the cell cycle. During the cell cycle, a cell makes a copy of its DNA and other contents, and divides in two. When cell cycle regulation doesn't happen correctly, cells may divide in an uncontrolled way, and diseases such as cancer can occur.

cell-to-cell signaling

The transfer of information from one cell to another.

cellular adhesion

The close adherence (bonding) to adjoining cell surfaces.

cellular adoptive immunotherapy

A treatment used to help the immune system fight cancer. A cancer patient's T cells (a type of white blood cell) are collected and grown in the laboratory to increase the number of T cells that are able to kill the person's cancer cells. These cancer-specific T cells are given back to the patient to help the immune system fight the cancer.

cellular metabolism

The sum of all chemical changes that take place in a cell through which energy and basic components are provided for essential processes, including the synthesis of new molecules and the breakdown and removal of others.

cellulitis

An acute, spreading infection of the deep tissues of the skin and muscle that causes the skin to become warm and tender and may also cause fever, chills, swollen lymph nodes, and blisters.

centimeter

A measure of length in the metric system. A centimeter is one hundredth of a meter. There are 2½ centimeters in an inch.

central nervous system

CNS. The brain and spinal cord.

central nervous system metastasis (...meh-TAS-ta-sis)

CNS metastasis. Cancer that has spread from the original (primary) tumor to the central nervous system (CNS).

central nervous system primitive neuroectodermal tumor

CNS PNET. A type of cancer that arises from a particular type of cell within the brain or spinal cord.

central nervous system prophylaxis (...pro-fih-LAK-sis)

CNS prophylaxis. Chemotherapy or radiation therapy given to the central nervous system (CNS) as a preventive treatment. It is given to kill cancer cells that may be in the brain and spinal cord, even though no cancer has been detected there. Also called CNS sanctuary therapy.

central nervous system sanctuary therapy

CNS sanctuary therapy. Chemotherapy or radiation therapy given to the central nervous system (CNS) as a preventive treatment. It is given to kill cancer cells that may be in the brain and spinal cord, even though no cancer has been detected there. Also called CNS prophylaxis.

A tube surgically placed into a blood vessel for the purpose of giving intravenous fluid and drugs. It also can be used to obtain blood samples. This device avoids the need for separate needle insertions for each infusion or blood test. Examples of these devices include Hickman catheters, which require clamps to make sure the valve is closed, and Groshong catheters, which have a valve that opens as fluid is withdrawn or infused and remains closed when not in use.

CEP-2563 dihydrochloride

A growth factor antagonist that may stop tumor cells from growing.

CEP-701

A substance that is being studied in the treatment of cancer. It belongs to the family of drugs called protein tyrosine kinase inhibitors.

cephalexin

An antibiotic drug that belongs to the family of drugs called cephalosporins.

cephalosporin

A drug used to treat bacterial infections. It belongs to the family of drugs called antibiotics.

ceramide

A type of fat produced in the body. It may cause some types of cells to die and is being studied in cancer treatment.

c-erbB-2

The gene that controls cell growth by making the human epidermal growth factor receptor 2. Also called HER2/neu.

cerebellar hemangioblastoma

A benign, slow-growing tumor in the cerebellum (part of the brain at the back of the head), made up of abnormal blood vessel growth. People with von Hippel-Landau disease have an increased risk of developing hemangioblastomas.

cerebellopontine (SER-uh-BEL-o-PON-teen)

Having to do with two structures of the brain, the cerebellum (located at the lower back of the brain) and the pons (located at the base of the brain in front of the cerebellum) and the area between them.

cerebellum (ser-uh-BEL-um)

The portion of the brain in the back of the head between the cerebrum and the brain stem. The cerebellum controls balance for walking and standing, and other complex motor functions.

cerebral hemisphere (seh-REE-bral HEM-is-feer)

One half of the cerebrum, the part of the brain that controls muscle functions and also controls speech, thought, emotions, reading, writing, and learning. The right hemisphere controls the muscles on the left side of the body, and the left hemisphere controls the muscles on the right side of the body.

cerebrospinal fluid (seh-REE-broe-SPY-nal)

CSF. The fluid flowing around the brain and spinal cord. Cerebrospinal fluid is produced in the ventricles in the brain.

cerebrospinal fluid diversion

A process used to drain fluid that has built up around the brain and spinal cord. A shunt (a long, thin tube) is placed in a ventricle of the brain and threaded under the skin to another part of the body, usually the abdomen. The shunt carries excess fluid away from the brain so it may be absorbed elsewhere in the body.

cerebrum (seh-REE-brum)

The largest part of the brain. It is divided into two hemispheres, or halves, called the cerebral hemispheres. Areas within the cerebrum control muscle functions and also control speech, thought, emotions, reading, writing, and learning.

cervical (SER-vih-kul)

Relating to the neck, or to the neck of any organ or structure. Cervical lymph nodes are located in the neck. Cervical cancer refers to cancer of the uterine cervix, which is the lower, narrow end (the "neck") of the uterus.

cervical cancer (SER-vih-kul KAN-ser)

Cancer that forms in tissues of the cervix (organ connecting the uterus and vagina). It is usually a slow-growing cancer that may not have symptoms, but can be found with regular Pap smears (procedure in which cells are scraped from the cervix and looked at under a microscope).

CIN. A general term for the growth of abnormal cells on the surface of the cervix. Numbers from 1 to 3 may be used to describe how much of the cervix contains abnormal cells.

cervix (SER-viks)

The lower, narrow end of the uterus that forms a canal between the uterus and vagina.

cetuximab

A type of monoclonal antibody being studied in the diagnosis and treatment of cancer. Monoclonal antibodies are laboratory-produced substances that can locate and bind to cancer cells.

cevimeline

A substance that increases production of saliva and tears. It is being studied as a treatment for dry mouth caused by radiation therapy to the head and neck. It belongs to the family of drugs called cholinergic enhancers.

CGP 48664

A substance that is being studied in the treatment of cancer. It belongs to the family of drugs called S-adenosylmethionine decarboxylase inhibitors.

Chamberlain procedure

A procedure in which a tube is inserted into the chest to view the tissues and organs in the area between the lungs and between the breastbone and heart. The tube is inserted through an incision next to the breastbone. This procedure is usually used to get a tissue sample from the lymph nodes on the left side of the chest. Also called anterior mediastinotomy.

chaplain (CHA-plin)

A member of the clergy in charge of a chapel or who works with the military or with an institution, such as a hospital.

chemoembolization

A procedure in which the blood supply to the tumor is blocked surgically or mechanically and anticancer drugs are administered directly into the tumor. This permits a higher concentration of drug to be in contact with the tumor for a longer period of time.

chemoimmunotherapy

Chemotherapy combined with immunotherapy. Chemotherapy uses different drugs to kill or slow the growth of cancer cells; immunotherapy uses treatments to stimulate or restore the ability of the immune system to fight cancer.

chemoprevention (KEE-mo-pre-VEN-shun)

The use of drugs, vitamins, or other agents to try to reduce the risk of, or delay the development or recurrence of, cancer.

A quality of some drugs used in cancer treatment. Chemoprotective agents protect healthy tissue from the toxic effects of anticancer drugs.

chemoradiation

Treatment that combines chemotherapy with radiation therapy. Also called chemoradiotherapy.

chemoradiotherapy

Treatment that combines chemotherapy with radiation therapy. Also called chemoradiation.

chemosensitivity

The susceptibility of tumor cells to the cell-killing effects of anticancer drugs.

chemosensitivity assay

A laboratory test that measures the number of tumor cells that are killed by a cancer drug. The test is done after the tumor cells are removed from the body. A chemosensitivity assay may help in choosing the best drug or drugs for the cancer being treated.

chemosensitizer

A drug that makes tumor cells more sensitive to the effects of chemotherapy.

chemotherapeutic agent

A drug used to treat cancer.

chemotherapy (kee-moh-THAYR-uh-pee)

Treatment with drugs that kill cancer cells.

chest wall

The muscles, bones, and joints that make up the area of the body between the neck and the abdomen.

chest x-ray

An x-ray of the structures inside the chest. An x-ray is a type of high-energy radiation that can go through the body and onto film, making pictures of areas inside the chest, which can be used to diagnose disease.

chiasma (ki-AZ-ma)

An anatomy term for an X-shaped crossing (for example, of nerves or tendons).

child-life worker

A professional who is responsible for making a child's hospital and treatment experience less scary.

Chinese rhubarb

Rheum palmatum or Rheum officinale. The root of this plant has been used in some cultures to treat certain medical problems. It may have anti-inflammatory and anticancer effects. Also called rhubarb, da-huang, Indian rhubarb, and Turkish rhubarb.

chitin

A type of polysaccharide (sugar molecule) that is made by some plants and animals. The hard outer shell of shrimp, lobsters, and many insects is made of chitin.

chlorambucil

An anticancer drug that belongs to the family of drugs called alkylating agents.

chlorine

A chemical used to disinfect water and as a bleach.

chloroma

A malignant, green-colored tumor of myeloid cells (a type of immature white blood cell). This tumor is usually associated with myelogenous leukemia. Also called granulocytic sarcoma.

chloroquinoxaline sulfonamide

CQS. A substance that is being studied in the treatment of cancer. It belongs to the family of drugs called halogenated sulfanilamides.

cholangiocarcinoma

A rare type of cancer that develops in cells that line the bile ducts in the liver. Cancer that forms where the right and left ducts meet is called Klatskin tumor.

cholangiosarcoma (ko-LAN-jee-o-sar-KO-ma)

A tumor of the connective tissues of the bile ducts.

cholecalciferol (KOH-leh-kal-SIH-fuh-rol)

A nutrient that helps the body use calcium and phosphorus and make strong bones and teeth. It is found in fatty fish, eggs, and dairy products. The skin can also make cholecalciferol when exposed to sunshine. Not getting enough cholecalciferol can cause a bone disease called rickets. Cholecalciferol is being studied in the prevention and treatment of some types of cancer. Also called vitamin D.

cholelith

Solid material that forms in the gallbladder or common bile duct. Choleliths are made of cholesterol or other substances found in the gallbladder. They may occur as one large stone or as many small ones, and vary from the size of a golf ball to a grain of sand. Also called gallstone.

cholestasis

Any condition in which the release of bile from the liver is blocked. The blockage can occur in the liver (intrahepatic cholestasis) or in the bile ducts (extrahepatic cholestasis).

cholesterol (kuh-LESS-tuh-rawl)

A waxy, fat-like substance made in the liver, and found in the blood and in all cells of the body. Cholesterol is important for good health and is needed for making cell walls, tissues, hormones, vitamin D, and bile acid. Cholesterol also comes from eating foods taken from animals such as egg yolks, meat, and whole-milk dairy products. Too much cholesterol in the blood may build up in blood vessel walls, block blood flow to tissues and organs, and increase the risk of developing heart disease and stroke.

chondrocyte

Cartilage cell. Chondrocytes make the structural components of cartilage.

chondroitin sulfate

The major glycosaminoglycan (a type of sugar molecule) in cartilage.

chondrosarcoma (KAHN-dro-sar-KO-ma)

A type of cancer that forms in cartilage.

chordoma (kor-DO-ma)

A type of bone cancer that usually starts in the lower spinal cord.

chorioallantoic membrane

The membrane in hen's eggs that helps chicken embryos get enough oxygen and calcium for development. The calcium comes from the egg shell.

choriocarcinoma

A rare cancer in women of childbearing age in which cancer cells grow in the tissues that are formed in the uterus after conception. Also called gestational trophoblastic disease, gestational trophoblastic neoplasia, gestational trophoblastic tumor, or molar pregnancy.

choroid plexus tumor

A rare type of cancer that occurs in the ventricles of the brain. It usually occurs in children younger than 2 years.

CHPP

Continuous hyperthermic peritoneal perfusion. A procedure that bathes the abdominal cavity in fluid that contains anticancer drugs. This fluid is warmer than body temperature. This procedure appears to kill cancer cells without harming normal cells.

chromosome (KRO-mo-some)

Part of a cell that contains genetic information. Except for sperm and eggs, all human cells contain 46 chromosomes.

chronic (KRAHN-ik)

A disease or condition that persists or progresses over a long period of time.

chronic eosinophilic leukemia

A disease in which too many eosinophils (a type of white blood cell) are found in the bone marrow, blood, and other tissues. Chronic eosinophilic leukemia may stay the same for many years, or it may progress quickly to acute leukemia.

chronic granulocytic leukemia

A slowly progressing disease in which too many white blood cells (not lymphocytes) are made in the bone marrow. Also called chronic myelogenous leukemia or chronic myeloid leukemia.

chronic idiopathic myelofibrosis

A progressive, chronic disease in which the bone marrow is replaced by fibrous tissue and blood is made in organs such as the liver and the spleen, instead of in the bone marrow. This disease is marked by an enlarged spleen and progressive anemia. Also called agnogenic myeloid metaplasia, primary myelofibrosis, myelosclerosis with myeloid metaplasia, and idiopathic myelofibrosis.

chronic leukemia (KRAHN-ik)

A slowly progressing cancer that starts in blood-forming tissues such as the bone marrow, and causes large numbers of white blood cells to be produced and enter the blood stream.

A slowly progressing disease in which too many immature white blood cells (called lymphoblasts) are found in the body.

chronic lymphocytic leukemia (KRAHN-ik lim-fo-SIT-ik loo-KEE-mee-a)

CLL. A common type of indolent (slowly progressing) cancer in which too many lymphocytes (white blood cells) are found in the peripheral blood and bone marrow. Most patients with CLL are older than 50 years and have no symptoms at the time of their diagnosis.

CML. A slowly progressing disease in which too many white blood cells (not lymphocytes) are made in the bone marrow. Also called chronic myeloid leukemia or chronic granulocytic leukemia.

chronic myeloid leukemia (KRAHN-ik MY-eh-loyd loo-KEE-mee-a)

CML. A slowly progressing disease in which too many white blood cells (not lymphocytes) are made in the bone marrow. Also called chronic myelogenous leukemia or chronic granulocytic leukemia.

chronic myelomonocytic leukemia

CMML. A slowly progressing type of myelodysplastic/myeloproliferative disease in which too many myelomonocytes (a type of white blood cell) are in the bone marrow, crowding out other normal blood cells, such as other white blood cells, red blood cells, and platelets.

chronic neutrophilic leukemia

A disease in which too many neutrophils (a type of white blood cell) are found in the blood. The extra neutrophils may cause the spleen and liver to become enlarged. Chronic neutrophilic leukemia may stay the same for many years or it may progress quickly to acute leukemia.

chronic pain

Pain that can range from mild to severe, and persists or progresses over a long period of time.

chronic phase (KRAHN-ik)

Refers to the early stages of chronic myelogenous leukemia or chronic lymphocytic leukemia. The number of mature and immature abnormal white blood cells in the bone marrow and blood is higher than normal, but lower than in the accelerated or blast phase.

chronic phase chronic myelogenous leukemia

A phase of chronic myelogenous leukemia in which 5% or fewer of the cells in the blood and bone marrow are blast cells (immature blood cells). This phase may last from several months to several years, and there may be no symptoms of leukemia.

CHS 828

A drug that is being studied in the treatment of solid tumors.

CI-1033

A substance that is being studied in the treatment of cancer. It belongs to the family of drugs called tyrosine kinase inhibitors.

CI-958

A substance that is being studied in the treatment of cancer. It belongs to the family of drugs called DNA-intercalating compounds. Also called sedoxantrone trihydrochloride.

CI-980

An anticancer drug that belongs to the family of drugs called mitotic inhibitors. Also called mivobulin isethionate.

CI-994

A substance that is being studied in the treatment of non-small cell lung cancer. Also called N-acetyldinaline.

cidofovir

A drug used in the treatment of infections caused by viruses.

cilengitide

A substance that is being studied as an anticancer and antiangiogenesis drug. Also called EMD 121974.

cimetidine

A drug usually used to treat stomach ulcers and heartburn. It is also commonly used in a regimen to prevent allergic reactions.

Cipro

A drug used to treat infections caused by bacteria. It is also being studied in the treatment of bladder cancer. Cipro belongs to the family of drugs called fluoroquinolones. Also called ciprofloxacin.

ciprofloxacin (sip-roe-FLOX-a-sin)

A drug used to treat infections caused by bacteria. It is also being studied in the treatment of bladder cancer. Ciprofloxacin belongs to the family of drugs called fluoroquinolones. Also called Cipro.

circulatory system

The system that contains the heart and the blood vessels and moves blood throughout the body. This system helps tissues get enough oxygen and nutrients, and it helps them get rid of waste products. The lymph system, which connects with the blood system, is often considered part of the circulatory system.

cirrhosis

A type of chronic, progressive liver disease in which liver cells are replaced by scar tissue.

CIS

Cancer Information Service. The CIS is the National Cancer Institute's link to the public, interpreting and explaining research findings in a clear and understandable manner, and providing personalized responses to specific questions about cancer. Access the CIS by calling 1-800-4-CANCER (1-800-422-6237), or by using the Web site at http://cis.nci.nih.gov.

cisplatin

An anticancer drug that belongs to the family of drugs called platinum compounds.

citric acid/potassium-sodium citrate

A drug used in the treatment of metabolic acidosis (a disorder in which the blood is too acidic).

c-kit receptor

A protein on the surface of some cells that binds to stem cell factor (a substance that causes certain types of cells to grow). Altered forms of this receptor may be associated with some types of cancer.

cladribine

An anticancer drug that belongs to the family of drugs called antimetabolites.

clarithromycin

An antibiotic drug used in the treatment of infections. It belongs to the family of drugs called macrolides.

clavicle

Collar bone.

clear cell

A type of cell that looks clear inside when viewed under a microscope.

clear cell adenocarcinoma

A rare type of tumor, usually of the female genital tract, in which the inside of the cells look clear when viewed under a microscope. Also called clear cell carcinoma and mesonephroma.

clear cell carcinoma (...KAR-sih-NOH-muh)

A rare type of tumor, usually of the female genital tract, in which the inside of the cells look clear when viewed under a microscope. Also called clear cell adenocarcinoma and mesonephroma.

clear cell sarcoma of the kidney

A rare type of kidney cancer. Clear cell sarcoma can spread from the kidney to other organs, most commonly the bone, but also including the lungs, brain, and soft tissues of the body.

cleaved

Having to do with the appearance of cells when viewed under a microscope. The nucleus of cleaved cells appears divided or segmented.

An exam of the breast performed by a health care provider to check for lumps or other changes.

clinical practice guidelines

Guidelines developed to help health care professionals and patients make decisions about screening, prevention, or treatment of a specific health condition.

clinical resistance

The failure of a cancer to shrink after treatment.

clinical series

A case series in which the patients receive treatment in a clinic or other medical facility.

clinical study

A type of research study that tests how well new medical approaches work in people. These studies test new methods of screening, prevention, diagnosis, or treatment of a disease. Also called a clinical trial.

clinical trial

A type of research study that tests how well new medical approaches work in people. These studies test new methods of screening, prevention, diagnosis, or treatment of a disease. Also called a clinical study.

CLL

Chronic lymphocytic leukemia. A common type of indolent (slowly progressing) cancer in which too many lymphocytes (white blood cells) are found in the peripheral blood and bone marrow. Most patients with CLL are older than 50 years and have no symptoms at the time of their diagnosis.

clodronate

A drug used in the treatment of hypercalcemia (abnormally high levels of calcium in the blood) and cancer that has spread to the bone (bone metastases). It may decrease pain, the risk of fractures, and the development of new bone metastases.

clofarabine

A substance that is being studied in the treatment of cancer. It belongs to the family of drugs called nucleoside analogs.

CML

Chronic myelogenous leukemia. A slowly progressing disease in which too many white blood cells are made in the bone marrow. Also called chronic granulocytic leukemia.

CMML

Chronic myelomonocytic leukemia. A slowly progressing type of myelodysplastic/myeloproliferative disease in which too many myelomonocytes (a type of white blood cell) are in the bone marrow, crowding out other normal blood cells, such as other white blood cells, red blood cells, and platelets.

CMV

Cytomegalovirus. A virus that may be carried in an inactive state for life by healthy individuals. It is a cause of severe pneumonia in people with a suppressed immune system, such as those undergoing bone marrow transplantation or those with leukemia or lymphoma.

cnicin

A substance found in certain plants, including blessed thistle. It has been used in some cultures to treat certain medical problems. It may have anti-inflammatory and anticancer effects. Cnicin belongs to a group of substances called sesquiterpene lactones.

CNS

Central nervous system. The brain and spinal cord.

CNS metastasis (meh-TAS-ta-sis)

Central nervous system metastasis. Cancer that has spread from the original (primary) tumor to the central nervous system (CNS).

CNS PNET

Central nervous system primitive neuroectodermal tumor. A type of cancer that arises from a particular type of cell within the brain or spinal cord.

CNS prophylaxis (pro-fih-LAK-sis)

Chemotherapy or radiation therapy given to the central nervous system (CNS) as a preventive treatment. It is given to kill cancer cells that may be in the brain and spinal cord, even though no cancer has been detected there. Also called CNS sanctuary therapy.

CNS sanctuary therapy

Central nervous system sanctuary therapy. Chemotherapy or radiation therapy given to the central nervous system (CNS) as a preventive treatment. It is given to kill cancer cells that may be in the brain and spinal cord, even though no cancer has been detected there. Also called CNS prophylaxis.

CNS tumor

Central nervous system tumor. A tumor of the central nervous system (CNS), including brain stem glioma, craniopharyngioma, medulloblastoma, and meningioma.

coactivated T cell

A T cell that has been coated with monoclonal antibodies to enhance its ability to kill tumor cells.

cobalamin (koh-BAH-luh-min)

A vitamin that is needed to make red blood cells and DNA (the genetic material in cells) and to keep nerve cells healthy. It is found in eggs, meat, poultry, shellfish, milk, and milk products. Cobalamin, along with folate, may be given to help reduce side effects in cancer patients being treated with drugs called antimetabolites. Also called vitamin B12.

cobalt 60

A radioactive form of the metal cobalt, which is used as a source of radiation to treat cancer.

Cockayne syndrome

A genetic condition characterized by short stature, premature aging, sensitivity to light, and possibly deafness and mental retardation.

co-culture

A mixture of two or more different kinds of cells that are grown together.

coenzyme Q10

A substance found in most tissues in the body, and in many foods. It can also be made in the laboratory. It is used by the body to produce energy for cells, and as an antioxidant. It is being studied in the treatment of cancer and in the relief of side effects caused by some cancer treatments. Also called Q10, CoQ10, vitamin Q10, and ubiquinone.

cohort study

A research study that compares a particular outcome (such as lung cancer) in groups of individuals who are alike in many ways but differ by a certain characteristic (for example, female nurses who smoke compared with those who do not smoke).

COL-3

A substance that is being studied in the treatment of cancer. COL-3 may block tumor growth by preventing the growth of new blood vessels into tumors. It belongs to the families of drugs called matrix metalloproteinase inhibitors and angiogenesis inhibitors.

cold nodule

When radioactive material is used to examine the thyroid with a scanner, nodules that collect less radioactive material than the surrounding thyroid tissue are considered "cold." A nodule that is cold does not make thyroid hormone. Cold nodules may be benign or cancerous. Cold nodules are sometimes called hypofunctioning nodules.

colectomy (ko-LEK-tuh-mee)

An operation to remove all or part of the colon. When only part of the colon is removed, it is called a partial colectomy. In an open colectomy, one long incision is made in the wall of the abdomen and doctors can see the colon directly. In a laparoscopic-assisted colectomy, several small incisions are made and a thin, lighted tube attached to a video camera is inserted through one opening to guide the surgery. Surgical instruments are inserted through the other openings to perform the surgery.

colitis

Inflammation of the colon.

collagen

A fibrous protein found in cartilage and other connective tissue.

collagen disease

A term previously used to describe chronic diseases of the connective tissue (e.g., rheumatoid arthritis, systemic lupus erythematosus, and systemic sclerosis), but now is thought to be more appropriate for diseases associated with defects in collagen, which is a component of the connective tissue.

collagenase

A type of enzyme that breaks down the protein collagen.

collecting duct

The last part of a long, twisting tube that collects urine from the nephrons (cellular structures in the kidney that filter blood and form urine) and moves it into the renal pelvis and ureters. Also called renal collecting tubule.

coloanal anastomosis

A surgical procedure in which the colon is attached to the anus after the rectum has been removed. Also called coloanal pull-through.

coloanal pull-through

A surgical procedure in which the colon is attached to the anus after the rectum has been removed. Also called coloanal anastomosis.

colon (KO-lun)

The longest part of the large intestine, which is a tube-like organ connected to the small intestine at one end and the anus at the other. The colon removes water and some nutrients and electrolytes from partially digested food. The remaining material, solid waste called stool, moves through the colon to the rectum and leaves the body through the anus.

colon cancer (KO-lun)

Cancer that develops in the tissues of the colon.

colon polyp

An abnormal growth of tissue in the lining of the bowel. Polyps are a risk factor for colon cancer.

colonoscope (ko-LAHN-o-skope)

A thin, lighted tube used to examine the inside of the colon.

colonoscopy (koh-luh-NAHS-kuh-pee)

An examination of the inside of the colon using a thin, lighted tube, called a colonoscope, inserted into the rectum. Samples of tissues may be collected for examination under a microscope.

colony-stimulating factor

A substance that stimulates the production of blood cells. Colony-stimulating factors include granulocyte colony-stimulating factors (also called G-CSF and filgrastim), granulocyte-macrophage colony-stimulating factors (also called GM-CSF and sargramostim), and promegapoietin.

colorectal (ko-lo-REK-tul)

Having to do with the colon or the rectum.

colorectal cancer (KOH-loh-REK-tul KAN-ser)

Cancer that develops in the colon (large intestine) and/or the rectum (the last several inches of the large intestine before the anus).

colostomy (ko-LAHS-toe-mee)

An opening into the colon from the outside of the body. A colostomy provides a new path for waste material to leave the body after part of the colon has been removed.

colposcope (KUL-puh-scope)

A lighted magnifying instrument used to examine the vagina and cervix.

colposcopy (kul-PAHS-ko-pee)

Examination of the vagina and cervix using a lighted magnifying instrument called a colposcope.

combination chemotherapy

Treatment using more than one anticancer drug.

combretastatin A4 phosphate

A substance that is being studied in the treatment of cancer. It belongs to the family of drugs called tubulin-binding agents.

comedo carcinoma

A type of ductal carcinoma in situ (very early-stage breast cancer).

comfort care

Care given to improve the quality of life of patients who have a serious or life-threatening disease. The goal of comfort care is to prevent or treat as early as possible the symptoms of the disease, side effects caused by treatment of the disease, and psychological, social, and spiritual problems related to the disease or its treatment. Also called palliative care, supportive care, and symptom management.

common bile duct

Carries bile from the liver and gallbladder into the duodenum (the upper part of the small intestine).

comorbidity

The condition of having two or more diseases at the same time.

compassionate use trial

A way to provide an investigational therapy to a patient who is not eligible to receive that therapy in a clinical trial, but who has a serious or life-threatening illness for which other treatments are not available. Also called expanded access trial.

complementary and alternative medicine

CAM. Forms of treatment that are used in addition to (complementary) or instead of (alternative) standard treatments. These practices generally are not considered standard medical approaches. Standard treatments go through a long and careful research process to prove they are safe and effective, but less is known about most types of CAM. CAM may include dietary supplements, megadose vitamins, herbal preparations, special teas, acupuncture, massage therapy, magnet therapy, spiritual healing, and meditation.

complementary medicine

Practices often used to enhance or complement standard treatments. They generally are not recognized by the medical community as standard or conventional medical approaches. Complementary medicine may include dietary supplements, megadose vitamins, herbal preparations, special teas, acupuncture, massage therapy, magnet therapy, spiritual healing, and meditation.

complete blood count

CBC. A test to check the number of red blood cells, white blood cells, and platelets in a sample of blood. Also called blood cell count.

complete hysterectomy (hiss-ter-EK-toe-mee)

Surgery to remove the entire uterus, including the cervix. Sometimes, not all of the cervix is removed. Also called total hysterectomy.

complete metastasectomy (meh-TAS-ta-SEC-tuh-mee)

Surgery to remove all metastases (tumors formed from cells that have spread from the primary tumor).

complete remission

The disappearance of all signs of cancer in response to treatment. This does not always mean the cancer has been cured. Also called a complete response.

complete response

The disappearance of all signs of cancer in response to treatment. This does not always mean the cancer has been cured. Also called a complete remission.

compound (KOM-pownd)

In science, a substance that is made up of more than one ingredient.

compound nevus (KOM-pownd NEE-vus)

A type of mole formed by groups of nevus cells found in the epidermis and dermis (the two main layers of tissue that make up the skin).

compression bandage

A bandage designed to provide pressure to a particular area.

computed tomographic colonography

CTC. A procedure in which a detailed picture of the colon is created by an x-ray machine linked to a computer. Also called computed tomography (CT) scan or computerized axial tomography (CAT) scan of the colon.

computed tomography (tuh-MAH-gra-fee)

CT scan. A series of detailed pictures of areas inside the body taken from different angles; the pictures are created by a computer linked to an x-ray machine. Also called computerized tomography and computerized axial tomography (CAT) scan.

computed tomography colography

A method under study to examine the colon by taking a series of x-rays (called a CT scan) and using a high-powered computer to reconstruct 2-D and 3-D pictures of the interior surfaces of the colon from these x-rays. The pictures can be saved, manipulated to better viewing angles, and reviewed after the procedure, even years later. Also called virtual colonoscopy.

A series of detailed pictures of areas inside the body taken from different angles; the pictures are created by a computer linked to an x-ray machine. Also called CAT scan, computed tomography (CT scan), or computerized tomography.

computerized tomography

A series of detailed pictures of areas inside the body taken from different angles; the pictures are created by a computer linked to an x-ray machine. Also called computerized axial tomography (CAT) scan and computed tomography (CT scan).

concurrent therapy

A treatment that is given at the same time as another.

conditioned stimulus

A situation in which one signal, or stimulus, is given just before another signal. After this happens several times, the first signal alone can cause the response that would usually need the second signal.

condyloma (kahn-dih-LO-ma)

A raised growth on the surface of the genitals caused by human papillomavirus (HPV) infection. The HPV in condyloma is very contagious and can be spread by skin-to-skin contact, usually during oral, anal, or genital sex with an infected partner. A female with condyloma is at an increased risk for developing cervical cancer. Also called genital wart and condylomata acuminata.

condylomata acuminata (kahn-dih-LO-ma-ta a-kyoo-mih-NA-ta)

A raised growth on the surface of the genitals caused by human papillomavirus (HPV) infection. The HPV in condylomata acuminata is very contagious and can be spread by skin-to-skin contact, usually during oral, anal, or genital sex with an infected partner. A female with condylomata acuminata is at an increased risk for developing cervical cancer. Also called condyloma and genital wart.

cone biopsy

Surgery to remove a cone-shaped piece of tissue from the cervix and cervical canal. Cone biopsy may be used to diagnose or treat a cervical condition. Also called conization.

congestive heart failure

Weakness of the heart muscle that leads to a buildup of fluid in body tissues.

conization (ko-nih-ZAY-shun)

Surgery to remove a cone-shaped piece of tissue from the cervix and cervical canal. Conization may be used to diagnose or treat a cervical condition. Also called cone biopsy.

conjunctiva

A membrane that lines the inner surface of the eyelid and also covers the front part of the eye. Conjunctivitis is inflammation of the conjunctiva.

conjunctivitis

A condition in which the conjunctiva (membranes lining the eyelids and covering the white part of the eye) become inflamed or infected. Also called pinkeye.

A clinical study that includes all eligible patients identified by the researchers during the study registration period. The patients are treated in the order in which they are identified. This type of study usually does not have a control group.

consolidation therapy

A type of high-dose chemotherapy often given as the second phase (after induction therapy) of a cancer treatment regimen for leukemia. Also called intensification therapy.

constipation (KAHN-stih-PAY-shun)

A condition in which stool becomes hard, dry, and difficult to pass, and bowel movements don't happen very often. Other symptoms may include painful bowel movements, and feeling bloated, uncomfortable, and sluggish.

contiguous

Touching or very close together.

contiguous lymphoma (kun-TIG-yoo-us lim-FOH-muh)

Lymphoma in which the lymph nodes containing cancer are next to each other.

continent reservoir (KAHN-tih-nent RES-er-vwar)

A pouch formed from a piece of small intestine to hold urine after the bladder has been removed.

contingency management

In medicine, a treatment plan that gives immediate rewards for desired changes in behavior. It is based on the principle that if a good behavior is rewarded, it is more likely to be repeated. This is often used in the treatment of drug and alcohol abuse, and is being studied as a smoking cessation method.

continuous hyperthermic peritoneal perfusion

CHPP. A procedure that bathes the abdominal cavity in fluid that contains anticancer drugs. This fluid is warmer than body temperature. This procedure appears to kill cancer cells without harming normal cells.

continuous infusion

The administration of a fluid into a blood vessel, usually over a prolonged period of time.

contraindication

A symptom or medical condition that makes a particular treatment or procedure inadvisable because a person is likely to have a bad reaction. For example, having a bleeding disorder is a contraindication for taking aspirin because treatment with aspirin may cause excess bleeding.

contralateral

Having to do with the opposite side of the body.

contrast material

A dye or other substance that helps show abnormal areas inside the body. It is given by injection into a vein, by enema, or by mouth. Contrast material may be used with x-rays, CT scans, MRI, or other imaging tests.

control animal

An animal in a study that does not receive the treatment being tested. Comparing the health of control animals with the health of treated animals allows researchers to evaluate the effects of a treatment more accurately.

control group

In a clinical trial, the group that does not receive the new treatment being studied. This group is compared to the group that receives the new treatment, to see if the new treatment works.

controlled clinical trial

A clinical study that includes a comparison (control) group. The comparison group receives a placebo, another treatment, or no treatment at all.

controlled study

An experiment or clinical trial that includes a comparison (control) group.

conventional therapy

A currently accepted and widely used treatment for a certain type of disease, based on the results of past research. Also called conventional treatment.

conventional treatment

A currently accepted and widely used treatment for a certain type of disease, based on the results of past research. Also called conventional therapy.

cooperative group

A group of physicians, hospitals, or both formed to treat a large number of persons in the same way so that a new treatment can be evaluated quickly. Clinical trials of new cancer treatments often require many more people than a single physician or hospital can care for.

CoQ10

A substance found in most tissues in the body, and in many foods. It can also be made in the laboratory. It is used by the body to produce energy for cells, and as an antioxidant. It is being studied in the treatment of cancer and in the relief of side effects caused by some cancer treatments. Also called coenzyme Q10, Q10, vitamin Q10, and ubiquinone.

cordectomy (kor-DEK-tuh-mee)

An operation on the vocal cords or on the spinal cord.

cordycepin

An anticancer drug that belongs to a family of drugs called antitumor antibiotics.

core biopsy

The removal of a tissue sample with a needle for examination under a microscope.

cornea

The transparent part of the eye that covers the iris and the pupil and allows light to enter the inside.

coronary artery disease (KOR-uh-nayr-ee AR-tuh-ree dih-ZEEZ)

CAD. A disease in which there is a narrowing or blockage of the coronary arteries (blood vessels that carry blood and oxygen to the heart). Coronary artery disease is usually caused by atherosclerosis (a build up of fatty material and plaque inside the coronary arteries). The disease may cause chest pain, shortness of breath during exercise, and heart attacks. The risk of coronary artery disease is increased by having a family history of coronary artery disease before age 50, older age, smoking tobacco, high blood pressure, high cholesterol, diabetes, lack of exercise, and obesity. Also called coronary heart disease.

coronary heart disease (KOR-uh-nayr-ee hart dih-ZEEZ)

A disease in which there is a narrowing or blockage of the coronary arteries (blood vessels that carry blood and oxygen to the heart). Coronary heart disease is usually caused by atherosclerosis (a build up of fatty material and plaque inside the coronary arteries). The disease may cause chest pain, shortness of breath during exercise, and heart attacks. The risk of coronary heart disease is increased by having a family history of coronary heart disease before age 50, older age, smoking tobacco, high blood pressure, high cholesterol, diabetes, lack of exercise, and obesity. Also called coronary artery disease (CAD).

corpus

The body of the uterus.

corticosteroid

A hormone that has antitumor activity in lymphomas and lymphoid leukemias. Corticosteroids (steroids) may also be used for hormone replacement and for the management of some of the complications of cancer and its treatment.

corticotropin (KOR-tih-koh-TROH-pin)

A form of the hormone adrenocorticotropic hormone (ACTH). It belongs to the family of drugs called corticosteroids.

cortisone

A natural steroid hormone produced in the adrenal gland. It can also be made in the laboratory. Cortisone reduces swelling and can suppress immune responses.

Corynebacterium granulosum

A bacterium that may stimulate the immune system to fight cancer.

co-trimoxazole

A drug used in the treatment of infections caused by bacteria and protozoa. It is a combination of two anti-infection drugs, sulfamethoxazole and trimethoprim.

coumestan

An estrogen-like substance (phytoestrogen) made by some plants. Coumestans may have anticancer effects.

coumestrol

A type of coumestan. Coumestans are estrogen-like substances (phytoestrogens) made by some plants. Coumestans may have anticancer effects.

COX inhibitor (kox in-HIH-bih-ter)

A type of drug that is used to treat inflammation and pain, and is being studied in the prevention and treatment of cancer. COX inhibitors belong to the family of drugs called nonsteroidal anti-inflammatory drugs (NSAIDs). Also called cyclooxygenase inhibitor.

COX-2 inhibitor

Cyclooxygenase-2 inhibitor. A nonsteroidal anti-inflammatory drug used to relieve pain and inflammation. COX-2 inhibitors are being studied in the prevention of colon polyps, and as anticancer drugs.

CP-358,774

A substance that is being studied in the treatment of cancer. It belongs to the family of drugs called epidermal growth factor receptor tyrosine kinase inhibitors. Also called erlotinib.

CP4071

A substance that is being studied in the treatment of cancer.

CP-547,632

A substance that is being studied in the treatment of cancer. It belongs to the families of drugs called vascular endothelial growth factor (VEGF) receptor inhibitors and angiogenesis inhibitors.

CP-609,754

A substance that is being studied in the treatment of cancer.

CP-724,714

A substance that is being studied in the treatment of cancer. It belongs to the family of drugs called ErbB receptor tyrosine kinase inhibitors.

CpG 7909

A substance that is being studied in the treatment of cancer. It belongs to the family of drugs called immune system stimulants.

CPT 11

An anticancer drug that belongs to a family of drugs called topoisomerase inhibitors. It is a camptothecin analogue. Also called irinotecan.

CQS

Chloroquinoxaline sulfonamide. A substance that is being studied in the treatment of cancer.

craniopharyngioma (KRAY-nee-o-fah-rin-jee-O-ma)

A benign brain tumor that may be considered malignant because it can damage the hypothalamus, the area of the brain that controls body temperature, hunger, and thirst.

craniotomy (kray-nee-AH-toe-mee)

An operation in which an opening is made in the skull.

creatine

A substance that is made by the body and used to store energy. It is being studied in the treatment of weight loss related to cancer. It is derived from the amino acid arginine.

creatinine (cree-AT-ih-nin)

A compound that is excreted from the body in urine. Creatinine levels are measured to monitor kidney function.

crib death

The sudden and unexpected death of a healthy child who is younger than one year old, usually during sleep. The cause of crib death is not known. Also called sudden infant death syndrome (SIDS).

cribriform

Pierced with small holes as in a sieve. Refers to the appearance of a tumor when viewed under a microscope. The tumor appears to have open spaces or small holes inside.

crisnatol mesylate

An anticancer drug that interferes with the DNA in cancer cells.

Crohn's disease (krone)

Chronic inflammation of the gastrointestinal tract, most commonly the small intestine and colon. Crohn's disease increases the risk for colorectal cancer and small intestine cancer. Also called regional enteritis.

cruciferous vegetable

A member of the family of vegetables that includes kale, collard greens, broccoli, cauliflower, cabbage, Brussels sprouts, and turnips. These vegetables contain substances that may protect against cancer.

cryopreservation

The process of cooling and storing cells, tissues, or organs at very low or freezing temperatures to save them for future use.

cryosurgery (KRY-o-SER-juh-ree)

A procedure performed with an instrument that freezes and destroys abnormal tissues.

cryotherapy

Any method that uses cold temperature to treat disease.

cryptorchidism (kript-OR-kid-izm)

A condition in which one or both testicles fail to move from the abdomen, where they develop before birth, into the scrotum. Cryptorchidism may increase the risk for development of testicular cancer. Also called undescended testicles.

CSF

Cerebrospinal fluid. The fluid flowing around the brain and spinal cord. CSF is produced in the ventricles of the brain.

CT scan

Computed tomography scan. A series of detailed pictures of areas inside the body taken from different angles; the pictures are created by a computer linked to an x-ray machine. Also called computerized tomography and computerized axial tomography (CAT) scan.

CT-2103

A protein that can be linked to a chemotherapy drug to deliver the drug directly to the tumor with fewer side effects. It is being studied in the treatment of cancer. Also called polyglutamate paclitaxel.

CT-2106

A form of the anticancer drug camptothecin that may have fewer side effects and work better than camptothecin. It is being studied in the treatment of cancer. It belongs to the family of drugs called DNA topoisomerase inhibitors. Also called polyglutamate camptothecin.

CT-2584

A substance that is being studied in the treatment of cancer. It may prevent the growth of blood vessels from surrounding tissue into a solid tumor.

CTC

Computed tomographic colonography. A procedure in which a detailed picture of the colon is created by an x-ray machine linked to a computer. Also called computed tomography (CT) scan or computerized axial tomography (CAT) scan of the colon.

cultured cell

A human, plant, or animal cell that has been adapted to grow in the laboratory.

cultured cell line

Cells of a single type (human, animal, or plant) that have been adapted to grow continuously in the laboratory and are used in research.

cumulative dose

In medicine, the total amount of a drug or radiation given to a patient over time; for example, the total dose of radiation given in a series of radiation treatments.

curcumin

A yellow pigment of the spice turmeric that is being studied in cancer prevention.

cure

To heal or restore health; a treatment to restore health.

curettage (kyoo-reh-TAHZH)

Removal of tissue with a curette (a spoon-shaped instrument with a sharp edge).

curette (kyoo-RET)

A spoon-shaped instrument with a sharp edge.

cutaneous (kyoo-TAY-nee-us)

Having to do with the skin.

cutaneous breast cancer

Cancer that has spread from the breast to the skin.

cutaneous T-cell lymphoma

A disease in which certain cells of the lymph system (called T lymphocytes) become cancerous (malignant) and affect the skin.

cyanogenic glucoside

A plant compound that contains sugar and produces cyanide.

cyanosis

Blue-colored skin caused by too little oxygen in the blood.

cyclooxygenase inhibitor

A type of drug that is used to treat inflammation and pain, and is being studied in the prevention and treatment of cancer. COX inhibitors belong to the family of drugs called nonsteroidal anti-inflammatory drugs (NSAIDs). Also called COX inhibitor.

cyclooxygenase-2 inhibitor

COX-2 inhibitor. A nonsteroidal anti-inflammatory drug used to relieve pain and inflammation. COX-2 inhibitors are being studied in the prevention of colon polyps, and as anticancer drugs.

cyclophosphamide

An anticancer drug that belongs to the family of drugs called alkylating agents.

cyclosporine

A drug used to help reduce the risk of rejection of organ and bone marrow transplants by the body. It is also used in clinical trials to make cancer cells more sensitive to anticancer drugs.

cyproheptadine (si-pro-HEP-ta-deen)

A drug that is used to treat asthma, allergies, and colds, and to relieve itching caused by certain skin disorders. It has also been used to stimulate appetite and weight gain, and is being studied in the treatment of weight loss caused by cancer and its treatment. Cyproheptadine belongs to the family of drugs called antihistamines.

cyproterone acetate

A synthetic hormone being studied for treatment of hot flashes in men with prostate cancer who have had both testicles removed by surgery.

cyst (sist)

A sac or capsule in the body. It may be filled with fluid or other material.

cystectomy (sis-TEK-tuh-mee)

Surgery to remove all or part of the bladder.

cystic fibrosis

A common hereditary disease in which exocrine (secretory) glands produce abnormally thick mucus. This mucus can cause problems in digestion, breathing, and body cooling.

cystosarcoma phyllodes

CSP. A type of tumor found in breast tissue. It is often large and bulky and grows quickly. It is usually benign (not cancer), but may be malignant (cancer). Also called phyllodes tumor.

cystoscope (SIS-toe-skope)

A thin, lighted instrument used to look inside the bladder and remove tissue samples or small tumors.

cystoscopy (sist-OSS-ko-pee)

Examination of the bladder and urethra using a thin, lighted instrument (called a cystoscope) inserted into the urethra. Tissue samples can be removed and examined under a microscope to determine whether disease is present.

cytarabine

An anticancer drug that belongs to the family of drugs called antimetabolites.

cytochlor

A substance that is being studied in the treatment of cancer. It belongs to the family of drugs called radiosensitizers.

cytochrome P450 enzyme system

A group of enzymes involved in drug metabolism and found in high levels in the liver. These enzymes change many drugs, including anticancer drugs, into less toxic forms that are easier for the body to excrete.

cytogenetics (SITE-o-juh-NET-iks)

The study of chromosomes and chromosomal abnormalities.

cytokine

A substance that is produced by cells of the immune system and can affect the immune response. Cytokines can also be produced in the laboratory by recombinant DNA technology and given to people to affect immune responses.

cytology

The study of cells using a microscope.

cytomegalovirus

CMV. A virus that may be carried in an inactive state for life by healthy individuals. It is a cause of severe pneumonia in people with a suppressed immune system, such as those undergoing bone marrow transplantation or those with leukemia or lymphoma.

cytopenia

A reduction in the number of blood cells.

cytoplasm

The fluid inside a cell but outside the cell's nucleus. Most chemical reactions in a cell take place in the cytoplasm.

cytotoxic

Cell-killing.

cytotoxic chemotherapy

Anticancer drugs that kill cells, especially cancer cells.

cytotoxic T cell

A type of white blood cell that can directly destroy specific cells. T cells can be separated from other blood cells, grown in the laboratory, and then given to a patient to destroy tumor cells. Certain cytokines can also be given to a patient to help form cytotoxic T cells in the patient's body.